Transition metal sulfide and nickel-iron layered double hydroxide nanohybrids for promising alkaline seawater oxidations

Direct seawater electrolysis is of great significance to produce green hydrogen using sustainable resources which can be applicable for water-scarce regions. Herein, a nanohybrid consisted of transition metal sulfide and layered double hydroxide is designed with aims to modify unfavorable surface electronic state of nickel-iron LDH (NF-LDH) for seawater oxidation. Specifically, Mo-doped NiS2 is deposited onto the self-standing two dimentional NF-LDH nanosheets, (Ni,Mo)S2//NF-LDH 300, using an e-beam evaporator. Physical deposition technique. The designed (Ni, Mo)S2//NF-LDH 300 catalyst proves a superior catalytic activity and stability for seawater oxidation under alkaline electrolyte. The deposited transition sulfide layer induces an improved charge transfer as well as reaction kinetics for the (Ni, Mo)S2//NF-LDH 300. Further, adsorptions of chloride anions at the surface is substantially suppressed due to the deposited transition metal sulfide effectively preventing chloride corrosions. The (Ni, Mo)S2//NF-LDH 300 demonstrates practical level of performance for alkaline seawater oxidation, shedding lights on our catalyst design strategy for direct seawater electrolysis.